Part 3: Radiographs: Not just about bitewings

Oct. 1, 2001
Long gone are the days of the typical protocol for bitewing X-rays — once believed to be the single most valuable X-ray attainable. Dental radiography has certainly come a long way. In fact, bitewing X-rays are becoming a thing of the past in clinical hygiene.

by Tammy L. Carullo, RDH, PC, PS

Long gone are the days of the typical protocol for bitewing X-rays — once believed to be the single most valuable X-ray attainable. Dental radiography has certainly come a long way. In fact, bitewing X-rays are becoming a thing of the past in clinical hygiene.

While bitewings likely will never be completely phased out, still playing an integral role in diagnostic care, more appropriate and advanced choices get the job done. We must avoid clinical complacency at all costs, and this holds true for radiology.

But what could have changed since you were in school? Lots! Every facet of dental hygiene is forever changing and improving. But unless you have graduated recently, you may be at a slight disadvantage in exactly what direction dental radiography has taken.

The traditional approach
For almost a century, bitewings have been integral to the diagnosis of dental caries. However, are they the superior film of choice in diagnosing other dental abnormalities? Take oral pathology, for example; 72 percent of all oral pathology can be first viewed on a panoramic film, but not on bitewings. One of the main concerns with bitewings is the very limited scope of vision. A better radiograph for diagnosing pathology may be either a panoramic or cephlometric film (side-cranial view used in orthodontic cases). On the other hand, these two types of film would offer very little in establishing periodontal status.

The standard periapical is still the optimal film for the diagnosis of periodontal disease. Individual vertical PAs provide an in-depth view of each potentially involved area.

What about vertical bitewings? They, too, have their place. But how many patients want 18 individual films, a panoramic, and a cephalometric taken at their first visit? Not many. Most dental practices still receive ample resistance from patients with regards to the X-ray issue.

So the real question is how can we get the information we need to accurately diagnose, but with minimal exposure and inconvenience to the patient?

If you are purely a traditional practice and are not yet ready to leap into the new era of dental radiography, some rather simple ways accomplish this seemingly endless goal. The first word that always comes to my mind when discussing patient X-rays is individualization. Individualization is key in all aspects of treatment. I am a firm believer that patient care should be conducted on an "as needed" basis. This philosophy includes dental X-rays.

Not every patient is going to be periodontally involved, eliminating the need for your standard FMS on every patient. However, every patient could definitely benefit from a panoramic film for ruling out oral pathology.

What are the most appropriate and best films for patients?

What's new?
Innovations are being made in the area of radiography — digital radiography, to be more precise — that will minimize exposure, create optimal images, and provide superior diagnostic and educational tools for our patients.

One of the most amazing strides in this newly found field of "micro-radiology" is the CDR (computed dental radiography). If you have not had an opportunity to work with this extraordinary piece of technology, brace yourself. CDR is the future of dental radiography and the ultimate tool in patient education.

The CDR delivers superior images instantly, and there are no chemicals to handle, no hassles with duplicating, no lost films that cannot be retrieved from insurance companies, and far less radiation exposure to patients and yourself. CDR also includes a CDR/Pan that offers the benefits of digital imaging for a panoramic film. It can fit on most existing panoramic units with no permanent modifications made to the unit.

Many of our patients are concerned about exposure to radiation. The CDR approach is safer, faster, and requires 90 percent less radiation. The images are instantaneously at your disposal, very easily e-mailed to insurance carriers, and accessible for providing patients with a level of chairside education never before dreamed possible.

CDR has revolutionized the way the dental world takes radiographs. As a computerized imaging system, CDR is a film-less X-ray system providing instant results and enhanced diagnostic tools. The digital radiographs can be displayed, stored, printed, and sent anywhere via modem. CDR produces images rated better than film.

Detecting signs and symptoms
Many patients who are unaware of dental problems — ranging from periodontal disease to oral implications of diabetes — would do well to consult a surprising source for help — the dental hygienist. But many patients squawk at the mere mention of X-rays. Try as we might to convince them of the need for the films, and that our hands are in a proverbial tied-knot otherwise, the average dental patient is literally like pulling teeth to get them to allow us to use these necessary diagnostic tools.

We have made great advances in patient acceptance over the years. By taking medical and oral histories, monitoring blood pressure, conducting head and neck exams, and focusing on extensive oral exams, hygienists are gaining a reputation as experts in preventive intervention. They are alerting patients to the possibilities that they may have life-altering systemic illnesses that directly correlate to oral health. However, our biggest challenge by far is still the acceptance of dental X-rays by our patients. We need to do more than just educate our patients that we cannot see decay without the films. The direct links between oral health, periodontal disease, and systemic diseases warrant the need for this open communication to our patients.

Many hygienists consider it a part of their job to detect the presence of illnesses such as diabetes. Although hygienists don't make a diagnosis, they explain what is discovered and urge patients to see a physician or dentist. According to the National Osteoporosis Foundation, osteoporosis affects 25 million Americans and accounts for 1.5 million fractures each year. Older women are most susceptible, but low calcium intake, inadequate physical activity, and a family history of the disease can put anyone at risk.

A hygienist is in a position to notice these risk factors and symptoms while taking a medical history and conducting a thorough exam. Dental X-rays play a valuable role in indicating the presence of osteoporosis. As is the case with osteoporosis, eating disorders such as anorexia nervosa and bulimia nervosa are far more common in women than men. In both disorders — but especially bulimia, a condition where compulsive eating is followed by self-induced vomiting — oral manifestations are clearly visible through dental X-rays.

What does the dental patient think during a visit involving traditional X-rays? The all-too-familiar scenario might sound like this in the patient's mind:

"When she returns from the 'file room,' the dental hygienist has my last X-rays in her hands. She announces that the doctor said it is time for more X-rays. 'Open wider,' she says. 'Now bite down.' She is pointing a tube at my jaw. She stands behind a wall, and turns on the machine. Then it's a trip down the hall to a 'developing tank,' where she says she will be processing for a few minutes. When she returns, she has the new X-rays with her. I am confused. Why did she need to leave the room? More importantly, why must there be a wall between us when she just explained how little radiation exposure I will receive? I wonder if I, too, should be on the other side of that wall?"

The emergence of digital radiography will, in all likelihood, make such thoughts a distant memory.

While patients will still need to "open wide" and "bite down," they will be biting down on a very thin electronic sensor, not hard plastic film holders and rigid film that irritates their soft tissues. The sensors were definitely built with comfort in mind. With the X-rays of old, patients' eyes produced tears by the time we actually shot the film and hurried back to remove it from their rather sore mouths.

With this exciting new technology, instead of an inconvenient trip to the dark room, dentist/hygienist and patient will watch images come up on a computer screen seconds after the device is inserted into the patient's mouth. The images are a higher resolution than film images and are stored in computer memory from which they can be easily accessed, retrieved, combined, and manipulated to supply more information. The chemical waste associated with film processing is completely eliminated, and, of course, radiation exposure is dramatically reduced.

One concern about conventional X-ray methods is that the film is generally sandwiched between sheets of plastic called intensifying screens. The disadvantage of the screens is that they scatter radiation, resulting in decreased spatial resolution and accuracy.

The technology developed for digital radiographic devices involves a light-emitting material, or scintillator, which provides a better spatial resolution for a given sensitivity to X-rays. Vacuum evaporation is a technique in which the scintillator cesium iodide is deposited on raised disks, or pucks, dotting the surface of a piece of high-temperature plastic. In the process of evaporation, the cesium iodide forms columns on the plastic pucks. When X-rays hit these columns, the material emits light (scintillation), which is partially lined up (collimated). Sideways scattering is minimized for better resolution and accuracy.

Digital radiography is clearly changing the world of dental X-rays. With the ability to capture images without film and chemicals and then enhance them, digital systems are quickly gaining popularity.

However, as with any new technology, CDR and the digital revolution is costly. The average small practice may not be able financially to make the same advancements as those who are better equipped.

There is a place for traditional X-rays. But, to avoid that complacency rut, you must keep up-to-date on the ever-changing world of radiography and move forward into the future of digital. Whether you are a new graduate or a seasoned veteran, the advancements in the world of digital radiography is exciting and will help you keep the "boredom" at bay.

Tammy L. Carullo, RDH, PC, PS, is CEO of Practice by Design, Inc. She is a practice-management consultant and continuing-education instructor. She may be contacted by e-mail at [email protected]

Common X-ray formats

Panoramic — Used for orthodontics, oral surgery, and diagnosis of oral pathology. Panoramics provide a comprehensive view of jaw, bone structure, TMJ, and oral pathology.Pro: Gives a wide angle over view of entire jaw area.Cons: Distorted image, unable to see interproximally, not an adequate film for periodontal diagnosis.Horizontal bitewings — Traditional film used for diagnosing interproximal decay. Horizontal bitewings provide a great view of the interproximal tooth surfaces and, because of the angle, an adequate view of the density of periodontal bone structure.Pro: Gives an in-depth view of tooth structure and immediate bone support.Con: Very limited in vertical dimension, thus providing limited diagnostic capability for perio. Also, far too many practices take only the traditional two and are not providing enough data to achieve the most comprehensive diagnosis possible. In addition, unable to see apex.Vertical bitewings — Common recall film for periodontally involved patients. Vertical bitewings provide a more in-depth view of not only interproximal areas, but a more detailed picture of the periodontal structures.Pro: Able to see more perio than the traditional BWX.Con: Unable to see apex.Periapical — Generally used for diagnosis of perio or periapical infections. Periapicals provides individual views of specific areas of interproximal, perio, and periapical views.Pro: Gives the best images of individual teeth and surrounding structures. Also able to diagnose periodontal or periapical infection or issues provided by apical view.Con: The standard 18 scares off most patients. However, if you limit the number and maximize the position of the film you may negate this drawback.

There is definitely no disputing that all of the aforementioned traditional approaches in dental radiography have their place. However, for the progressive dental practice, they may very soon be put in the inactive file as digital radiography becomes more common.

Advantages of CDR

  • Instant images save time
  • Large images can be manipulated
  • Better patient communication
  • Improved communication with insurance companies
  • More consistent image quality
  • Dramatic reduction in radiation exposure
  • Instant retakes
  • Potential for electronic claims processing
  • Potential for future advances (three-dimensional radiography, second-generation digital subtraction, teleradiography, etc.)